Investigations have been done to clarify intraocular fluid movement in rhesus monkeys and humans. Monkey aqueous humor has been analyzed for glycosaminoglycans, glycoprotein, and hyaluronidase content. Human and monkey trabecular meshwork organ culture has allowed us to start defining normal and glaucomatous tissue proteoglycans production and to define the effect of glaucoma treatment on outflow tissue production of proteoglycans.